Method for the production of expanded trussed beams



Aug. 21, 1928. 1,681,400

H. M. GERSMAN METHOD FOR THE PRODUCTION OF EXPANDED TRUSSED BEAMS FiledOct. 9, 1924 Patented Aug. 21 1928.

UNITED STATES HARVEY M; GERSMAN, OF CHICAGO, ILLINOIS.

METHOD FOR-ITHE PRODUCTION or manner) rnussnn BEAMS.

Application filed. October 9, 1924. Seria1No. 742,712.

This invention relates to a method for the production of expandedtrussed beams and more particularly forthe production of an expandedbeam from an original rolled section, preferably an I-beam section.

The principal object of the invention is to provide a method by which a.novel and advantageous form of expanded trussed beam may be producedfrom an original integral section by procedure of simple and economicalcharacter and in which the application of heat is not required and themetal of the blank is not stretched. a

A further object is to provide amethod by which an expandedtrussed-be-am produced from an original section which will havesuflicient strength for all practical purposes and in which the an le ofthe struts may be selected as desired without any liability offracturing.

The accompanying drawin s illustrate the practice of the method and anexpanded trussed I-beam resulting therefrom.

Insaid drawings:

Figure 1 is an elevation of the slitted blank.

Figure 2 is a section on the line 22 of Fi ure 1.

Figure 3 is an elevation of the blank after the offsetting of theportions which provide the struts. v

Figure 4 is a section on the line 44 of Figure 3.

Figure 5 is an elevation of the blank after ex ansion.

igure 6 is a section on the line 6-6 of Fi ure 5.

Figure 7 is an elevation of the completed in Figures 1 and 2, whichconsists of a rolled I-beam shape of the usual or any desired sectionhaving a central planar web 1 and top and bottom flanges 2 and 3. Theweb 1 is slitted in characteristic fashion to provide for expansion inaccordance with the inven-' tion. Thus the web is provided with paralleldiagonal slits/i which extend from points near one flange to points nearthe other and with short alinin longitudinal slits 5 which,

as shown, extend etween corresponding ends of adjoining slits 4.Therebytheslits 4 are connected in successive pairs adjacent one oftheflanges with the result that the metal between the slits not connectedhas the form of continuous strands 6 and the metal between theconnectedslits has the form of interrupt edor discontinuous strands, that istosay of tongues 7, which alterna e with the" strands 6. As shown andpreferred the slits4 ten minate at points short of the flanges, there-byleaving beyondthe slits solid web portions 1 and 1 but, if desired, theslits a maybe continued right up to the flanges and these may be made ofsuch thickness as mav be deemed advisable. The strands 6 are laterallyofl'set so as to lie in a common plane at the same side of the meanplane of the web. This ofi'setting of the strands is accomplished by acorrugating operation in the manner disclosed inmy pending application,Serial N 0. 642,872, that is to say the web is longitudinally channelledor corrugated in the portions constituted by the strands, the slitsextending into andalong the sides of the chana nel or corrugation. Thetongues 7' which, as shown, project fromthe solid portion 1, are. inlike manner bent so as to lie in a common plane at the opposite side ofthe'mean plane of the web. The corrugating' and bending operations bywhich the strands and tongues are thus laterally offset whereby theblank has the form shown in Figures 3 and 4 may be performed inconnection with the slitting or at a later stage. The strands andtongues are also preferably curved between their ends so asto haveconvex faces adjacent the mean plane of the web, as shown in Figure 4,and suchc-urving may be done at the time of slitting or at a laterstage.

The blank is now ready for expansion and this is accomplished by movingthe flanges in relatively opposite directions while maintainingtheirangular relation to the mean plane of the web whereby the strands arecaused toapproach more nearly to perpendicular positions,- as shown inFigure 5. Such expansion of the blank follows generally the procedureoutlined in my said pending application, Se rial No. 642,872 butproduces no changein' the positionsof the tongues 7 and the beam iscompleted by bending the tongues in the general direction of theircommon plane so as to cause them to extend oppositely, that is: to say.in intersecting relation to the strands as produced by the expansion,after which the free ends of the tongues are suitably secured, as byspot welding, to the adjacent solid section of the web, the completedbeam bein shownin Figures 7 and 8. Such bcnding o with the expansion orat a later stage. If de sired, and for the purpose ot providing a truelattice truss, the tongues and strands may be suitably secured, as byspot welding, to one another at their points of intersection, asindicated at 8 in Figure 7.

It will be obvious that the strands may be bent in the direction oftheir common plane to greater or less degree and that the degree towhich the tongues are bent in their common plane will depend on thedegree to which the strands are bent. As shown the strands have beenbent to positions short of perpendicular and the tongues have been bentthrough and beyond perpendicular but if desired the strands may be bentthrough and beyond perpendicular in which casethe tongues will be bentto positions suitably short of perpendicular.

It will be observed that the angle of the struts are not limited by theductility and elasticity of the metal and that any angle is practicalwithout liability of fracture.

Instead of locating the short slits 5 at the ends of the diagonal slits& they may be lo cated as desired at points along the length of i theslits 4, for example at midway points.

Such location of the slits 5 will result in the discontinuous strandseach being in the form of a. pair of originally alining tonguesprojecting from the respective solid portions 1 and 1 or from therespective flanges 2 and 3 in case the solid portions are not employed.After expansion of the continuous strands as above described theoriginally alining tongues which, during expansion, have becomerelatively longitudinally ofliset, are bent back into alining relationand their ends connected by welding, the same welding operation beingavailable to connect them to the continuous strands which theyintersect.

Having fully described my invention, I claim:

1. A method for the production of an expanded trussed beam from astructural section having oppositely located flanges and a solid planarweb integral with the flanges which consists in slitting the web toprovide parallel diagonal continuous strands and interrupted strandsparallel to and alternating with the continuous strands, in effectingthe expansion of the web. in bending the interrupted strands from thepositions in which they are left by the expansion into intersectingrelation to the continuous strands and parallel relation to one anotherand securing the interrupted strands at their points of interruption toadjacent parts of the web.

2. A method for the productionof an expanded trussed beam from astructural section having oppositely located flanges and asolid planarweb integral with the flanges which consists in slitting the web toprovide parallel diagonal continuous strands and interrupted strandsparallel to and alternating with the continuous strands, in relativelylaterally offsetting the continuous and interrupted strands, ineffecting the expansion of the web, in bending the interrupted strandsfrom the positions in which they are left by the expansion intointersecting relation to the continuous strands and parallel relation toone another and securing the interrupted strands at their points ofinterruption to adjacent parts of the web.

A method for the production of an ex panded trussed beam from astructural section having oppositely located flanges and a solid planarweb integral with the flanges which consists in slitting the web toprovide parallel diagonal continuous strands and in terruptcd strandsparallel to and alternating with the continuous strands, in eli'ectingthe expansion of the web, in bending the interrupted strands intopositions in which they may be secured at their points of interruption,and securing the bent interrupted strands at their points ofinterruption to adjacent parts of the web.

l. A method for the production of an expanded trussed beam from astructural section having oppositely located flanges and a. solid planarweb integral with the flanges which consists in slitting the web toprovide parallel diagonal continuous strands and interrupted strandsparallel to and alternating with the continuous strands, in relativelylatter-ally offsetting the continuous and interrupted strands, ineiiecting the expansion of the web, in bending the interrupted strandsinto positions in which they may be secured at their points ofinterruption, and securing the bent interrupted strands at their pointsof interruption to adjacent parts of the web.

5. A method for the production of an expanded trussed beam from astructural section having oppositely located flanges and a solid planarweb integral with the flanges which consists in providing paralleldiagonal slits in said web with the slits of successive pairs connectedby longitudinal slits, thereby to provide continuous parallel strandsintegral at both ends with the web and interrupted strands alternatingwith the continuous strands, in relatively laterally oflsetting thecontinuous and interrupted strands, in relatively shifting the flangesto expand the portion of the web constituted by the strands, and inbending the interrupted strands to extend oppositely and in intersectingrelation to the continuous strands and connecting the interruptedstrands at their points of interruption to adjacent parts of the web.

6. A method for the production of an expanded trussed load bearingmember from a structural section having a planar web which consists inproviding parallel diagonal slits in said web with solid portions beyondthe slits and the slits of successive pairs connected by longitudinalslits, thereby to provide continuous parallel strands integral at bothends with said solid portions and interrupted strands alternating withthe continuous strands, in relatively laterally ofisetting the strandsand the tongues, in relatively shifting the solid portionslongitudinally in their common plane to expand the portion of the webconstituted by the strands, and in bending the interrupted strands topositions wherein they may be attached at their points of interruptionto adjacent parts of the web and in attaching said interrupted strandsat their points of interruption to adjacent parts of the web.

7. A method for the production of an expanded trussed load bearingmember from a structural section having a planar'web which consists inproviding parallel diagonal slits in said web with the slits ofsuccessive pairs connected by longitudinal slits, thereby to producecontinuous parallel strands integral at both ends with the web andinterrupted strands alternating with the continuous strands, inoffsetting the continuous strands and the interrupted strands laterallyat opposite sides of the mean plane of the web, in relatively shiftingthe flanges to expand the portion of the web constituted by thecontinuous strands, and in bending the interrupted strands to positionswherein they may be attached at their points of interruption to adjacentportions of the web and in attaching the bent interrupted strands attheir points of interruption.

8. A method for the production of an expanded trussed load bearingmember from a structural section having a planar web which consists inproviding parallel diagonal slits in said web with the slits ofsuccessive pairs connected by longitudinal slits, thereby to producecontinuous parallel strands integral at both ends with said web andinterrupted strands alternating with the continuous strands, in forminga longitudinal channel in the portion of the web constituted by thecontinuous strands with the ends of the slits extending into the sidesof the channel, thereby to oliset the continuous strands laterally withrespect to the mean plane of the web, in relatively shifting theflangesto expand the portion of the Web constituted by the continuousstrands, and in bending the interrupted strands to positions whereinthey may be attached to adjacent portions of the web at their points ofinterruption and in attaching the bent interrupted strands at theirpoints of interruption to adjacent portions of the web.

9. A method for the production of an expanded trussed load bearingmember from a structural section having a planar web which consists inproviding parallel diagonal slits in said Web with the slits ofsuccessive pairs connected by longitudinal slits, thereby to produceparallel strands integral at both ends with the web and interruptedstrands alternating with the continuous strands, in forming alongitudinal channel in the portion of the web constituted by thecontinuous strands with the ends of the slits extending into the sidesof the channel, thereby to offset the continuous strands laterally withrespect to the mean plane oi the web, in laterally ofisetting theinterrupted strands at the opposite side of the mean plane of the web,in rela tively shifting the flanges to expand the portion of the webconstituted by the continuous strands, and in bending the interruptedstrands to positions wherein they may be attached to adjacent portionsof the web at their points of interruption and in attaching the bentinterrupted strands at their points of interruption to adjacent portionsof the web.

10. A blank for use in the production of an expanded trussed loadbearing member con sisting of a rolled structural section having aplanar web provided with parallel diagonal slits with the slits ofsuccessive pairs connected by longitudinal slits, thereby to providecontinuous strands and interrupted strands alternating with thecontinuous strands.

11. A blank for use in the production of an expanded trussed loadbearing member consisting of a. rolled structural section having aplanar web provided with parallel diagonal slits with the slits ofsuccessive pairs connected by longitudinal slits, thereby to providecontinuous strands and interrupted strands alternating with thecontinuous strands, the continuous strands and the interrupted strandsbeing relatively laterally offset.

12. In the production of an expanded trussed load bearing member from astructural section having a planar web, providing parallel diagonalslits in said web with the slits of successive pairs connected bylongitudinal slits thereby to produce continuous strands and interruptedstrands alternating with the continuous strands, relatively laterallyofl'setting the continuous strands and the interrupted strands, andrelatively moving the flanges to alter the angle and increase the mutualspacing of the continuous strands.

13. A blank for use in the production of an expanded trussed loadbearing member consisting of a rolled structural section having a planarweb provided with parallel diagonal slits and solid portions beyond theends of the slits with the slits of successive pairs connected bylongitudinal slits, thereby to provide continuous strands andinterrupted strands alternating with the continuous strands.

In testimony whereof I aiiixmy signature.

HARVEY M. GERSMAN.

